Homebrew PCBs

I went out yesterday to Staples and got a letter sized Rubbermaid 
hanging folder holder, and to a pet shop and got an air pump, heater, 
hose and air stone.  It sound like I should return the air stone and 
just pierce the tubing a bunch to let the air out, instead.  The 
rubbermaid thing is about 13 x 9 x 4, internal, with a lip around the 
inside for hanging folders (or pcb holders).  It has a hinged top (the 
hinge is just a fold between the top  bottom) that snaps on, and a 
carrier handle that 'locks' the top down.  It's marked with 5 in the 
recycle symbol, and PP.  I'm assuming that its poly propylene.  I have a 
plastic pail in the garage with a snap on top that came holding bulk cat 
litter, but it looks like 2.5 gallons or so, and has no easy to use 
places for hanging board holders.  I have some 1.25 inch, 80 psi sewer 
pipe, which is black, not white.  I don't know the chemistry.  I was 
thinking about slicing it down one side so I can just shove the edge of 
the board in there, like an upside down flag, and just put it in the 
etchant with the long end sticking out.
  I got 2 gallons of hcl for $5 at home despot, and a quart of h2o2 for 
a buck at Savon.  Now all I have to do is use the stuff.
  Does anyone know of any limitations on etching chemistries for 
different types of  plastic?
  I've looked around some, and never seen any sites that say 'use 5 
parts hcl to 1 part h2o2 to 9 parts h2o', or whatever.  Does anyone know 
what the final % hcl and h2o2 the solution should start with?  I've seen 
how to keep the cucl2 going, but not how to start it right.
Thanks,
Richard